Nino is very closely bonded to Poppy, they are like chalk and cheese but joined at the hip most of the time. Every pair is different. We had Nino first and I too was worried it would change my relationship with him as because I am home a lot, especially when we first adopted him, he and I are very closely bonded too. When we got Poppy there was an intermediate stage of the relationship whilst he and her were growing closer and yes to begin with he began to choose to spend more time with her than me, which is fine because she can fulfil more of his needs than I can being a rabbit. However, now they are fully settled as a pair and have been for several years, he gradually reverted back to being my Nino after the initial bonding excitement of having another bun around.
Buns are capable of multiple relationships and are very good at sharing their time. Poppy likes to sleep a lot during the day, Nino doesn't, so if I'm around and Poppy is snoozing under the bed in the other room he spends the whole day hanging out with me as usual, sometimes Poppy comes and joins us too. If i'm out or busy he goes and finds Poppy instead. He shares his time between us, to be honest I normally have two rabbits stuck to my feet these days and lounging around where I am, we are a threesome for much of the day! :lol: Buns have plenty of room in their lives for more than one bunny/person and they will often share their time. I definitely feel that since we got Poppy he is just that little bit more content and feels just that little bit more secure with another bun around, he can express his rabbity ways with a rabbit and this is the best gift you can give another bun. He adores her and she adores him, but they both still adore me... so don't worry!
Incidentally, Nino licks everything around him, always has done, whether Poppy is around or not. I have had to remove a fluffy toy rabbit as he was grooming it excessively and all it's fur is now crispy with dried saliva! :roll::lol: Some buns just lick things.... it's probably a comfort and reflex behaviour to some extent, Poppy normally seizes the opportunity when he is in licking mode! :lol: